1. Field of the Invention
The present invention relates to data encryption. More specifically, the present invention relates to safeguarding the transfer of data within a device.
2. Background Information
With the proliferation of computers and networks, the amount and availability of digitized data available for viewing and listening has grown. However, with this growth in the amount and availability of information, content providers have desired greater protection of the data from unauthorized use.
In order to protect data from unauthorized use, conventional data protection techniques, such as, for example, data encryption, have been used to protect data as it is being transferred over a network or between devices. Content providers use a number of well known encryption techniques to encrypt sensitive data before transmission from one device, such as, for example, a satellite receiving dish, to a second device, such as, for example, a computer or set-top box.
Different conventional types of encryption techniques are used depending upon the source device of the data and the type of data bus being used for the transmission from one device to another. For example, data transmitted from a Digital Video Disk (DVD) player to a computer uses Content Scrambling System (CSS) encryption, and data transmitted over an IEEE 1394 bus use Digital Transmission Content Protection (DTCP). Data transmitted over other bus systems use a number of other encryption techniques. In order to decrypt the data as it is received, devices need to be able to decrypt data using the variety of techniques that are used to encrypt the data. Thus, a device that receives both CSS and DTCP encrypted data needs to know the techniques for decrypting both types of encrypted data.
The various encryption techniques employed only protect the data during transmission. Once the data is received, it must be decrypted in order for the receiving device to be able to process the data. Once the data is decrypted within the receiving device, the data is susceptible to unauthorized access and manipulation.
Moreover, these conventional systems do not protect the data inside an open architecture device, such as a personal computer. Conventional systems do not control what applications access the incoming data-stream, nor allow those applications to access the incoming data stream without being aware of the data originator outside the device.